How can I include or Call Session Controller In to My home page ,about page ....

If you want to write you session check as a library, you need to put your Session_check file into the library folder:

app
----library
--------Session_check.php

You can load it via $this->load->library('Session_check'); , if the file is called Session_check.php.

But you can't simply extends CI_Controller, you need to get an instance of CI, via get_instance();

Have a look here, if you don't know how to get CI instance.
http://forum.codeigniter.com/thread-61626.html

And for the purpose of learning, look here http://www.codeigniter.com/userguide3/ge...aries.html

But for simpleness, just write the Content of Session_check in the same controller or write it in a MY_Controller and extend it, instead of CI_Controller. But this is just a mention.

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